Currently, there are several classes of vasodilators for clinical use, for example, α1 receptor antagonists, including prazosin, doxazosin, terazosin, etc., but the significant first dose effect or postural hypotension of these drugs have limited their clinical application; Ca2+ channel blockers have been widely used in clinical application, including amlodipine, nifedipine, felodipine etc. But they also show risk of cardiac suppression.
Thus, there remains a need to develop new vasodilators to improve efficacy and reduce side effects, and to meet different clinical needs.